Vaalissek, a cataclysm mage who was started life with the name Velisse Trangere, has received a personal prophecy: force a demon to reveal its true face. However, thanks to clever innuendo from a Chamber agent who wishes to see the cataclysm mage destroy herself (or from a recurring villain who wishes the PCs to be destroyed), Velisse believes that one of the PCs or their followers is actually a rakshasa.
Vaalissek cries out, “Cease your dissembling, fiend!” as she threatens to assault the PCs with evocation spells from across a gap between towers in Sharn. Her improved pseudodragon familiar flies invisibly across the gap to deliver touch spells; after it becomes visible, any player making a DC 10 Spot check notices the tiny beast. Those who know that pseudodragons are good creatures are then likely to attempt to parley with Vaalissek.
A DC 25 Diplomacy check moves her attitude from unfriendly to indifferent, at which time she calls off her attack, takes stock of the situation, and probably ends up asking the PCs for aid in tracking down the treacherous Chamber agent.